VESSEL REVIEW | Sakhalin – Russia's first domestically built, heavy work-class ROV

Russian subsea services company Fertoing has begun sea trials of Sakhalin (Сахалин), a heavy work-class remotely operated vehicle (ROV) that its developers have described as the first of its type produced in Russia.

Trials started on August 26, 2026 at the Saint Petersburg flood-protection complex.

The vehicle is intended to replace the imported heavy work-class ROVs that Fertoing has operated on Russian shelf projects for more than a decade. Two such systems began work on the Sakhalin shelf in 2012, which gave the new vehicle its name.

"We have been operating similar imported vehicles for more than 10 to 15 years and have accumulated a great deal of experience, but due to the complex geopolitical situation and sanctions, getting components has become more difficult,” said Anton Sklyar, who heads Fertoing's department responsible for technical operations involving underwater robotics. “We decided to build our own vehicle, incorporating the best features from several systems."

Deep-diving capability suitable for inspection and installation work

The project is a strategic partnership between Fertoing and the People of the Sea Foundation. Russian Maritime Team is the direct engineering contractor, and Gazprom Shelfproject also participated.

Sakhalin is rated to 3,000 metres (9,800 feet). Development group leader Anton Merkulov gave its dimensions as 3.5 by two by two metres (11 by 6.6 by 6.6 feet) and its mass as approximately 4.5 tonnes. The vehicle is propelled by eight thrusters.

The ROV can carry two manipulators, one with five degrees of freedom and one with seven, along with interchangeable tooling. Local news outlet SPbit reported that the manipulators can handle tools ranging from angle grinders to torque wrenches.

According to SPbit, power is supplied from the support vessel through the tether, and control runs over a fibre-optic link to the vessel's control station.

Able to accommodate various payload combinations

An echosounder and sonar are fitted for search work, and all sealed compartments were tested in a pressure chamber at approximately 36 MPa. Publication RoboTrends listed payload at 250 to 1,000 kg (550 to 2,200 lb), depending on configuration.

Sklyar said development began in 2022–2023 and production commenced in 2024.

"The entire electronic component is entirely our own design, we do not use any parts from imported vehicles," he said.

Laboratory and factory testing preceded the sea trials.

Configured for 24-hour operation

Fertoing director Artem Melnikov estimated the domestic share of the vehicle's components at approximately 70 per cent at the launch. He said increasing that share is the next development objective.

The vehicle closely matches the Triton heavy work-class units in Fertoing's existing fleet. The Triton is rated to 3,050 metres (10,000 feet) and is also fitted with a five-function and a seven-function manipulator.

Three people operate Sakhalin on each shift: a chief pilot, a co-pilot who operates the manipulators, and a shift supervisor.

At sea, work runs 24 hours a day in two 12-hour shifts.

In 2027, the vehicle is scheduled to work on the Sea of Okhotsk shelf, supporting construction of a subsea production complex.

Planned tasks include inspection, object searches, equipment installation, connection of electrical and hydraulic lines, and adjustment work at depth.

Melnikov told Delovoy Peterburg that the first phase of sea trials had been successful and deepwater trials were being prepared. He placed trial operation in early 2027 and commercial operation in the second half of that year, followed by series construction.

The company is considering an initial series of five vehicles over three years, with the possibility of reaching 10 by 2035.